Machine for stretching leather used for making power-belts.



PATENTED DEC. 6, 1904.

E. L. POST.

MACHINE FOR STRETOHING LEATHER USED FOR MAKING POWER BELTS.

APPLICATION FILED SEPT. 2, 1903.

3 SHEETS-SHEET 1.

N0 MODEL.

k /7fl mmron 627% Z. Z 043 WI TIVESSES 11 TTORNEYS No. 776,685. PATENTED DEC. 6, 1904. E. L. POST.

MACHINE FOR STRETGHING LEATHER USED FOR MAKING POWER BELTS.

APPLICATION FILED SEPT. 2. 1903.

N0 MODEL. 3SHEETS-$HBBT 2.

4 TTORNEYS Nmwmesa. PATBNTED DEC; 6, 1904.

E. L. POST.

MACHINE FOR STRETOHING LEATHER USED FOR MAKING POWER BELTS.

APPLICATION FILED SEPT. 2, 1903.

N0 MODEL. 3 SHEETS-SHEET S.

i. 5mm

uu Lluu uuuuuuuuu y a wfiH I w f I .4. Immm, I Q ull HHHNI F I WITNESSES INVENTOH f V I JzraZfid-t K Z M I I TTORNEYS UNITED STATES Patented December 6, 1904.

EZRA L. POST, OF WALLINGFORD, CONNECTICUT.

MACHINE FOR STRETCHING LEATHER USED FOR MAKING POWER-BELTS.

SPECIFICATION forming part of Letters Patent No. 776,685, dated December 6, 1904.

Application filed September 2, 1903. Serial No. 171,645. (No model.)

To all, 1077,0791, it inn/y concern.-

Be it known that 1, EZRA L. Pos'r, a citizen of the United States, residing at Wallingford, in the county of New Haven and State of Connecticut, have invented certain new and useful Improvements in Machines for Stretching Leather Used for Making Power-Belts, of which the following is a specification, such as will enable those skilled in the art to which it appertains to make and use the same. The object of this invention is toprovide an improved machine for stretching leather from which power-belts are mad e, so that the belts when made from such leather will not stretch more at one edge than at the other.

It is a well-known fact that the hides from which belting-leather is made are tougher and stronger along the longitudinal center thereof than at the opposite edges, and when leather made from these hides is out into strips which are secured together to form power belts these belts are softer at one edge than at the other and will stretch more at such edges, and this makes the belt longer at one edge than at the other and prevents the same from properl y fitting the driving-pulleys and also throws more strain upon one edge of the belt than the other and causes the belt to run crooked or work off of the pulleys. It is also a wellknown fact that hides of the class referred to are thicker and softer at the edges or side portions thereof than at the longitudinal center, and in order to avoid the objections above specified to belts made from leather cut from such hides all portions of the leather can be so stretched that when the strips are cut longitudinally from the leather and sewed or otherwise secured together the entire belt so formed will possess throughout its length and breadth the same degree of firmness and strength and the same power of resistance in order that it will not stretch more at one point than at another or at one edge than at the other; and the object of this invention is to providea machine which will accomplish these results.

The invention is fully disclosed in the following specification, of which the accompanying drawings form a part, in which the separate parts of my improvement are designated by suitable reference characters in each of the views, and in which- Figure 1 a plan view of my improved leather-stretching machine and showing a strip or sheet of leather in position to be stretched, part of which is broken away; Fig. 2, a plan view of the framework of the machine; Fig. 3, an end view thereof; Fig. 4, a bottom plan view of a modified form of the machine shown in Fig. 1; Fig. 5, a side view of a clamp which I employ and showing also the method of mounting the same; Fig. 6, a plan view thereof; Fig. 7, a plan view of a part of the operative mechanism of the machine, and Fig; 8 a section on the line 8 8 of Fig. 7.

In the practice of my invention, as shown in Figs. 1 to 3, inclusive, I provide a main frame composed of two longitudinal and parallel side bars a, which are preferably cylindrical in form and also. preferably tubular, and these side bars are connected at one end by a cross-head 7), in which they are rigidly secured, and at the, opposite end by a crosshead 0, which is free to slide longitudinally thereon and which is provided with means to preventits movement in one direction, as hereinafter described. The cross-head 7) is provided with two longitudinal slots or openings 6 which are arranged in the same transverse line, and the cross-head c is provided with two similar longitudinal slots or openings o which are also arranged in thesame transverse line. On the cross-head b are placed two stretcherblocks (Z, which are preferably rectangular in form, and these blocks are provided at one side with extensions (i having slots or openings (Z which in the normal position of the stretcher-blocks are in a line transverse of the main frame of the machine. The slots d or the side walls thereof are provided with metal plates d, provided at their inner edges with ratchet teeth (Z and passing vertically through the slots in the cross-head 7) and through the slots cl in the blocks (Z are bolts 0, which also pass through a slide a, placed in the slots (Z and these bolts are provided at their upper and lower end-s in the form of construction shown with washers a", and one end thereof is provided with a head a and the other with a nut 0 and by means of these bolts the stretcher-blocks are free to turn on the cross-head b and also to swing in a hori- Zontal plane, and said stretcher-blocks may be moved longitudinally of said cross-head and adjusted to any desired point thereon, and the slots 6 are provided with pivoted spring-operated pawls e, which operate in connection with the ratchet-teeth (Z and which prevent the movement of the slides e and the stretcherblocks (Z on the cross-head 0 outwardly, except when such movement is desired. The cross-head c is provided on the under side thereof and adjacent to the side bars a with pivoted pawls 0 which operate in connection with corresponding ratchet-teeth a on the side bars a, and secured to the bottom of the crosshead 0 are springs a, which bear on said pawls and force them into contact or in connection with said teeth, and the pawls 0 are provided with hackwardly-directed handles 0 by which they may be operated or the connection thereof with the ratchet-teeth a broken. The crosshead 0 is also provided on the side thereof adjacent to the corresponding end of the bars a with eyes, hooks, or other attaching devices 0,with which in practice cords, cables, or similar devices 0 are connected. Mounted on the cross-head care stretcher-blocks (Z, exactly the same in the matter of their connection with the said cross head 0 as the corresponding stretcher-blocks on the cross-head Z), the details of which have been heretofore described. Each of the stretcher-blocks (Z on the crossheads 7) and c is provided with parallel slots or openings f, and these slots or openings run parallel with the main frame, and in the form of construction shown ten of these slots or openings are shown in each stretcher-block; but the number of said slots or openings may be varied within certain limits. In each of said stretcher-blocks is mounted a slide f and these slides are each provided at the inner ends thereof with a clamp g, which is pivoted thereto at f, and each of said clamps consist of a stationary jaw g an upwardly and forwardly directed arm g", and a supplemental jaw 9 which is pivoted to said arm at g and adapted to operate in connection with the jaw g". The head of the jaw 9*, through which the pivot-pin passes at is provided with a backwardly-directed finger g, and secured to the arm is a spring which bears on said finger and is adapted to normally force the jaw g downwardly into contact with the jaw 9 Pivoted to the jaw g at g is a rod h, which passes through an opening if in the arm g' of the clamp g and is provided with a tooth b and this tooth is adapted to engage the upper forward edge of the opening If, and by means of the rod It the pivoted jaw may be raised and held out of engagement with the jaw g or, in other words, may be held out of operation. The slides f in the slots or openings f in the stretcher-blocks 61 are oblong in form and provided with a lever i, pivoted to said slides at 2' and provided with a downwardly-directed front end pawl d adapted to engage notches or recesses c" in the opposite side walls of the slots or openings f, and by means of this construction the position of the slides f and the position of the clamps 9 may be adjusted longitudinally of the stretcherblocks and longitudinally of the main frame, as desired, and between the slides f and the lever Z is placed a spring 2' which holds the said levers in operative position and secures the slides f of said clamps at any desired point of adjustment. The operation of this form of construction will be readily understood from the foregoing description when taken in connection with the accompanying drawings and the following statement thereof. \Vhenever it is desired to stretch a piece of leather from which power-belting is to be made. the leather is cut from the prepared hide in the form shown at 7' in Fig. 1. The machine is placed on any suitable support and is so held as to prevent its longitudinal or other movement, this being accomplished in any desired way. The position of the crosshead 0 with reference to the sheet or strip of leather to be stretched is then adjusted to correspond with the length of said sheet of leather, and the opposite ends of said sheet of leather are connected with the clamps g. In cutting the sheet of leather 7' from a hide one end thereof, the tail end, is usually irregular in form, as indicated in Fig. 1, and the clamps Z must be adjusted to correspond with this irregularity. It will be understood, of course, that said clamps 9 may be adjusted to any desired position in theslots or openings f in the stretcher-blocks (Z, and this applies to all of said stretcher-blocks. l/Vhen the cross-head 0 has been properly positioned and the clamps 7 properly adjusted and the sheet j of leather connected therewith, power is applied to the cables, cords, or other devices 0 and the crosshead 0 is moved outwardly longitudinally of the side bars a of the main frame and away from the cross-head b, and this operation of course stretches the leather or the sheet 7' longitudinally. It will be apparent that if the pivot pins or bolts 6, which secure the stretcherblocks (Z to the cross-heads band 0, are properly adjusted in the slots or openings (Z the said stretcher-blocks will be free to swing laterally, as indicated by the dotted lines 0 in Fig. 1, and if these pivot pins or bolts are properly adjusted said stretcher-blocks as the power is applied to the cables or other devices 0 will turn laterally in the direction of the said dotted lines 0, and the extent of this turning will depend on the comparative toughness and elasticity of the longitudinal center and side portions of the leather sheetj. The pivot pins or bolts 6 are preferably placed at the transverse centers of the stretcher-blocks IIO in order to properly accomplish this result, and this is the position, or approximately the position, in which they are shown in Fig. 1. As the power is applied to the cables or other devices a the cross-head c is moved outwardly or away from the cross-head 7), and the leather 7' will be stretched to correspond to this movement of said cross-head. In this operation the longitudinal center of'the leather 7' being tougher and stronger than the sides thereof the said stretcher-blocks gradually turn outwardly, as indicated by the dotted lines 0, this movement resulting from the fact that the edges of the sheet y' of leather are softer and more stretchable than the center portion thereof, and as the power is applied to the cables 0 this movement continues, the blocks (Z gradually turn, and the sheet 1' of leather is gradually stretched to the limit throughout its entire extent. In Fig. 1 of the drawings the clamps g, which are connected with the stretcher-blocks mounted on the crosshead Z), are all secured to the leather in the same horizontal line; but in practice the position of said clamps may be adjusted to any desired extent in order to accomplish the desired result, and this can best be accomplished by setting the inner clamps of each stretcherblock farther back and the outer clamps farther inward or toward the longitudinal center of the main frame, and. this is also true of the clamps connected with the stretcherblocks which are mounted on the cross-head c, the object being to provide means whereby the side portions of the leather sheet may be stretched more than the central portion thereof and at the same time to stretch the leather sheet laterally as well as longitudinally.

It will be understood that the pivot-pins a form centers around which the stretcherblocks (Z turn, and it will be understood also that the movement of these blocks or the turning thereof on said centers or pivot-pins will depend on the position of said pins, and while in the form of construction shown the slots in the said stretcher blocks through which these pins or bolts pass are in the outer portions thereof or adjacent to the ends of the main frame the said pivot pins or bolts may be arranged differently and may be placed nearer the centers of the said stretcher-blocks, if desired, and said pivot pins or bolts may also be placed nearer the longitudinal center of the main frame. It will be understood also that the leather sheet] to be stretched is first Wet, so as to render it soft and pliable, and by the mechanism and process of operation herein described the said sheet is thoroughly stretched longitudinally and laterally, the turning of the stretcher-blocks (Z serving to stretch the side or edge portions of the sheet more than the center portion is stretched, this operation resulting from the fact that the stretcher-blocks turn on their pivotal supports at the same time that the cross-head c is moved outwardly on the main frame or on the side bars 0 thereof.

In Fig. 4 I have shown a modification which is intended for the purpose of stretching the sides only of a hide or a sheet of leather cut from a hide, the central longitudinal portion of which has been removed. In this form of construction the side bars (1/ and the cross heads 6 and c are exactly the same as the corresponding parts shown in Figs. 1 and 2, with the exception that there are no slots in the cross-heads through which the pivot pins or bolts 6 are passed. Fig. 4 is a bottom plan view, and in practice a cable or similar device is connected with the cross-head c at 0", and the sheet or strip of leather to be stretched is connected with the clamp devices with which the stretcher-blocks d are provided in the same manner as hereinbefore described with reference to the construction shown in Figs. 1 and 2. In this form of construction the stretcher-blocks (Z are also not provided with slots through which the pivot-pins or bolts 0 pass, and the only movement that said stretcher-blocks have, with the exception of the longitudinal movement of theblock which is connected with the cross-head 0, is a turnor side portion of said sheet will be stretched more than the other, and the said strip or sheet will be thus stretched throughout its entire extent, and after this has been accomplished it may be out into belt-strips,which are connected to form a belt in the usual manner.

My invention is not limited to the exact form and construction of the main frame nor to that of the clamp devices, and various changes in and modifications of these features of construction, as well as other parts of the apparatus herein shown and described, may be made without departing from the spirit of my invention or sacrificing its advantages, and I reserve the right to make all such alterations in and modification of the construction herein described as fairly come within the scope of my invention.

Having fully described my invention, what I claim as new, and desire to secure by Letters Patent, is- I 1. A machine for stretching leather, comprising a main frame provided with crossheads one of which is movable longitudinally of the main frame, stretcher-blocks pivoted ICC to said cross-heads and adapted to swing in a horizontal plane and adjustable on said crossheads transversely of the main frame and clamp devices connected with said stretcherblocks, substantially as shown and described.

2. A machine for stretching leather, comprising a main frame provided with crossheads one of which is movable longitudinally of the main frame, stretcher-blocks pivoted to said cross-heads and adapted to swing in a horizontal plane and adjustable on said crossheads transversely of the main frame and clamp devices connected with said stretcher blocks and adjustable thereon longitudinally of the main frame, substantially as shown and described.

3. A machine for stretching leather, comprising a main frame provided with crossheads, one of which is movable longitudinally of the main frame, automatic devices for preventing said last-named cross-head from moving in the direction of the other cross-head, stretcher-blocks pivoted to both of said crossheads and adapted to swing in a horizontal plane, and clamp devices connected with said stretcher-blocks, substantially as shown and described.

4:. A machine for stretching leather, comprising a main frame provided with crossheads, one of which is movable longitudinally of the main frame, automatic devices for preventing said last-named cross-head from moving in the direction of the other cross-head, stretcher-blocks pivoted to both of said crossheads and adapted to swing in a horizontal plane, and clamp devices connected with said stretcher blocks and adjustable on said stretcher-blocks longitudinally of the main frame, substantially as shown and described.

5. A machine for stretching leather, comprising a main frame provided with crossheads one of which is movable longitudinally thereof, stretcher-blocks pivoted on said crossheads and adapted to turn in a horizontal plane and adjustable transversely of the main frame, said stretcher-blocks being provided with parallel slots or openings, and clamp devices mounted in said slots or openings and adjustable on said stretcher-blocks longitudinally of the main frame, substantially as shown and described.

6. A machine of the class described, comprising a main frame provided with crossheads one of which is adjustable longitudinally thereof, stretcher-blocks mounted on said cross-heads and adapted to turn in a horizontal plane and provided with parallel grooves, and clamp devices mounted in said grooves and adjustable therein, and means for moving one of said cross-heads longitudinally of the main frame, substantially as shown and described.

In testimony that I claim the foregoing as my invention 1 have signed name, in presence of the subscribing Witnesses, this 31st day of August, 1903.

EZRA L. POST. Witnesses:

F. A. STEWART, G. E. MULREANY. 

